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Copyright (c) 1992-2006 GRISOFT, s.r.o. All rights reserved.

AVG Linux Email Server / User Manual

 
 
 
 
 
 
 

 
 
AVG 7.1 for Linux E-mail Server 

User Manual 
 
 
 
 
 
 
 
 
 

Document revision 71.7 (15.6.2006) 

Copyright (c) 1992-2006 GRISOFT, s.r.o. All rights reserved. 

This product uses RSA Data Security, Inc. MD5 Message-Digest Algorithm, Copyright (C) 1991-2, RSA 
Data Security, Inc.  Created 1991.  
This product uses code from C-SaCzech library, Copyright (c) 1996-2001 Jaromir Dolecek 
<[email protected]
This product uses compression library zlib, Copyright (C) 1995-2002 Jean-loup Gailly and Mark Adler 
This product uses libtar library, Copyright (c) 1998-2003 University of Illinois Board of Trustees, 
Copyright (c) 1998-2003  Mark D. Roth 
This product uses compression library libbzip2, Copyright (C) 1996-2002 Julian R Seward 
This product uses XML parser library expat, Copyright (C) 1998, 1999 James Clark 
This product uses library libcurl, Copyright (c) 1996 - 2003, Daniel Stenberg, <[email protected]
This product includes Flex software developed by the University of California, Berkeley and its 
contributors, Copyright (c) 1993 The Regents of the University of California 
All other trademarks are property of their respective owners. 

Summary of Contents for Anti-Virus 7.1

Page 1: ...compression library zlib Copyright C 1995 2002 Jean loup Gailly and Mark Adler This product uses libtar library Copyright c 1998 2003 University of Illinois Board of Trustees Copyright c 1998 2003 Mark D Roth This product uses compression library libbzip2 Copyright C 1996 2002 Julian R Seward This product uses XML parser library expat Copyright C 1998 1999 James Clark This product uses library lib...

Page 2: ...stallation 18 5 E mail Scanning 19 5 1 General Principles 19 5 2 Performance and Resource Usage 19 5 3 Using Unix Socket for an Extra Security 20 6 Commercial E mail Servers 21 6 1 AVG for Lotus Notes Domino Server Installation and Maintenance 21 6 2 AVG for Kerio MailServer Maintenance 29 7 Standalone Command Line Modules 33 7 1 AVGSCAN Command 33 7 2 AVGUPDATE Command 36 7 3 On access Scanner 40...

Page 3: ...ocal update sources b AVG for Linux E mail Server E mail Scanning Features The incoming and outgoing e mail messages processed by the supported mail transport agents MTA are watched by constantly running AVG Anti Virus process memory resident scanning daemon This means the e mail spooling queues are protected and scanned regularly by AVG for Linux E mail Server The AVG Anti Virus e mail scanning p...

Page 4: ...also provided at http www lifewithqmail org o postfix The postfix MTA is a popular alternative to the widely used sendmail e mail server the latest version is available for free at http www postfix org o exim This MTA can be also used as replacement for the common sendmail e mail server although its configuration and maintenance principles differ the latest version of the exim e mail server is ava...

Page 5: ...il Scanner to see how to install the Qmail Scanner mail virus scanner and how to integrate it with AVG for Linux E mail Server f DAZUKO Kernel Module The DAZUKO kernel module is necessary for the proper function of the AVG for Linux E mail Server on access scanner DAZUKO is available for free at http www dazuko org Refer to section 7 3 Standalone Command Line Modules On access Scanner for detailed...

Page 6: ...al components of AVG for Linux E mail Server are always updated properly to offer you the maximum security and reliability The versions 12 and newer are comprehensively installed into the opt grisoft directory Symbolic links are created in various system directories leading to the opt grisoft directory subtree If you want to upgrade the old directory structure you must completely reinstall your AV...

Page 7: ...on in the file etc pam d avggui a Distributions Currently Supported Distribution Installation package Mandrake Linux Red Hat Red Flag Fedora Core and other systems supporting the RPM packager utility avg71 edition r version a version of avi i386 rpm Any other Linux distribution e g Debian Slackware Gentoo etc avg71 edition r version a version of avi i386 tar gz b The Installation Process The insta...

Page 8: ...sm and AVG for Linux E mail Server configuration file See chapters 7 4 Standalone Command Line Modules Service Signals and 8 Configuration File for detailed information Launch the services as root only root can send signals to daemons etc init d avgd start If you are not logged in as root the command responds with respective warning You can use the su command and apply the superuser password to ch...

Page 9: ...9 For proper function of the on access scanning daemon the DAZUKO kernel module is required Refer to section 7 3 Standalone Command Line Modules On access Scanner for detailed information on this topic The included command line modules can be operated as described in chapter 7 Standalone Command Line Modules ...

Page 10: ...installing the AMaViS package amavis various versions supported you must apply the AVG Anti Virus patch Supposing you have unpacked the installation file switch to the unpacked directory copy the amavis version avg patch file there included in the AVG for Linux E mail Server installation package and apply the patch using the patch p1 amavis version avg patch command Run autoconf with the autoconf ...

Page 11: ...t being developed any longer although its source code can be obtained via the AMaViS CVS repository a Prerequisites The C language compiler and also the make and autconf automake utilities are needed to build the AMaViS tools The essential modules responsible for extracting e mail content and passing it to the AVG for Linux E mail Server scanning engine are implemented in Perl This is why the Perl...

Page 12: ...aViS installation b Installation To install AMaViS from the source code unpack the selected downloaded package the amavis package is given in the following example tar xvzf amavis version tar gz Switch to the unpacked directory It is recommended to read the detailed instructions in the INSTALL and or README file located in this directory The easiest way of performing the installation is to run the...

Page 13: ...t agent These README files contain detailed information and configuration examples for all supported mail transport agents 4 3 Qmail Scanner a Prerequisites The qmail version 1 03 or higher is needed Make sure the reformime tool for reformatting the MIME e mail format is installed on your computer The reformime package can be obtained for free at http prdownloads sourceforge net courier Also the P...

Page 14: ..._qmail o auto_split o auto_split o env a load qmail send qsutil o control o constmap o newfield o prioq o trigger o fmtqfn o quote o now o readsubdir o qmail o date822fmt o datetime a case a ndelay a getln a wait a seek a fd a sig a open a lock a stralloc a alloc a substdio a error a str a fs a auto_qmail o auto_split o substdio a error a str a fs a auto_qmail o auto_split o env a qmail send 0 qma...

Page 15: ...close pim 0 close pim 1 return 1 Before installing the software a special account must be created which the Qmail Scanner processes will run under By default the user group name for this account is qscand For extra security create it with a normal home directory e g home qscand but with a fake shell e g bin false as Qmail Scanner never logs in directly Make sure AVG for Linux E mail Server is inst...

Page 16: ...he EICAR anti virus test file and one obvious spam to the root s address Ideally Qmail Scanner should let one through catch the viruses and tag the spam as spammy if SpamAssassin is installed of course As Qmail Scanner initially defaults not to notifying anyone when a virus is caught you may have to view the logs e g syslog to see what Qmail Scanner exactly did c Configuration To enable Qmail Scan...

Page 17: ... mail coming from your Exchange server and not on mail from your Unix servers Note You must increase the amount of memory your system allows qmail smtpd to run with because it is now running the entire Perl language interpreter and also the AVG for Linux E mail Server Typical installations of qmail are provided with the system rc startup scripts e g etc rc d init d qmail or service smtp run These ...

Page 18: ...n be employed to perform the regular cleanup Note For details on the Qmail Scanner please refer to the http qmail scanner sourceforge net website 4 4 Testing the Installation Successful installation of AVG for Linux E mail Server and the appropriate mail content scanner AMAViS or Qmail Scanner can be tested within any supported e mail server by sending a message with the Eicar test file attachment...

Page 19: ...tion of the configuration file 127 0 0 1 by default The address must be the same as the one the mail transport agent is bound to The default port which the daemons are listening on is 55555 If necessary this value can be changed in the configuration file as well AVG for Linux E mail Server does not support direct configuration of actions to be performed after virus detection and or suspicion in th...

Page 20: ...figuration file You can also change the parameter value if necessary the default value is tmp avg sock See chapter 8 Configuration File for detailed information on the configuration file z In the opt grisoft avg7 etc init d avgdinit conf file change the SUSER parameter value to the name of the user who is supposed to run the e mail scanning AVG Anti Virus daemon for example amavis z Finally you mu...

Page 21: ...VG for Linux E mail Server can be performed using the special AVG for Lotus Notes Domino Linux plugin You can obtain the plugin in the form of a precompiled tar gz package on the AVG Anti Virus installation CD or in the Download Programs section at http www grisoft com Before you can install the plugin you need to z install and configure Lotus Domino Server for Linux z install and configure AVG fo...

Page 22: ...be present there NSF_HOOKS avghook servertasks avgmail avgscan AVGLang x where x is 1 2 or 3 depending on language you have selected The server tasks servertasks configuration line tells the Lotus Notes Domino Server to run the AVG for Lotus Notes Domino server services In order to complete the installation Lotus Notes Domino Server must be restarted This will automatically launch the AVG for Lotu...

Page 23: ...es Configuration window In this window select the appropriate server on which you want to have the AVG Anti Virus configuration database Double click its field or simply press the Edit button which is right above the servers list A new untitled window will then be opened within the administrator utility environment see the following two screenshots You can fully control the scanning and infected e...

Page 24: ...or virus infected files Possible actions are Remove the infected files are removed from the e mail Remove and store in Virus Vault the infected files are removed from the e mail and stored in local Virus Vault Store in Virus Vault and deliver to recipient the infected files are kept in the e mail and copies are also stored in local Virus Vault Deliver to recipient the infected files will be kept i...

Page 25: ...warning to recipient sender you can check this field if you wish to warn the recipient sender depending on whether you choose Deliver mail to the recipient or Return mail to the sender action on virus found of virus infected e mail Text of warning here you can edit the default message text which is included in the virus infected e mail if you have the Send warning to recipient sender field checked...

Page 26: ... database scan You can edit the text of the warning message in the corresponding Text of warning field The administrator is able to define the text of the subject line of an e mail to be sent In the warning e mail body there a list of infected files with links and the viruses found b AVG Virus Vault AVG Virus Vault is a special Lotus Notes Domino server database which the virus infected files can ...

Page 27: ...s tab and a new window will be opened There are two fields present for both the Databases and Mail folders Those are o Date the timestamp of the logged record o Text the text of the log information d Uninstalling the AVG for Lotus Notes Linux Plugin If you want to install newer version of AVG for Lotus Notes Linux plugin you must uninstall the older version first You can perform the uninstallation...

Page 28: ...lotus notesdata notes ini in a text editor and delete the avgmail and avgscan strings from the line beginning with ServerTasks idetifier Delete also the whole lines NSF_HOOKS AVGHOOK AVGLang x The x depends on the language installed 1 for Czech 2 for English and 3 for German o From the usr local lotus notes latest linux directory delete the files avgscan avgmail libavghook so After performing the ...

Page 29: ... z Attachment Filter z Action To save the changes press the Apply button in the bottom area of the configuration window You can also return to the previously saved state by pressing the Reset button a Antivirus Tab To activate AVG for Kerio MailServer select the Use external antivirus radio button and choose the Grisoft AVG for Linux Edition 7 1 item from the external software menu on the Antiviru...

Page 30: ...ven in the Content field Possible types are File name or MIME type You can select the respective box in this field to include exclude the item in from attachment filtering o Content an extension to be filtered can be specified here You can use operation system wildcards here for example the string doc stands for any file with the doc extension and any other extension following o Action define acti...

Page 31: ... In the Description field you can write a short description of the attachment to be filtered o In the If a mail message contains an attachment where field you can select the type of attachment File name or MIME type You can also choose a particular extension from the offered extensions list or you can type the extension wildcard directly o In the Then field you can decide whether to block the defi...

Page 32: ...s sent back to the message sender that his her message was virus infected and or filtered Having selected this item the Only if sender is local checkbox will be active You can specify whether to send the warning to all senders or to the local ones only your domain users Bounce the message to sender when selected the infected or filtered message is returned to its sender Discard the message when se...

Page 33: ...ommand itself can manage only the on demand test you can also use it to create scheduled tests by incorporating the cron Linux system utility See the manual pages man cron crontab or the respective documentation for detailed information The options for the avgscan command and their descriptions are given in the following table Parameter Description scan Simple generic scan of the given objects and...

Page 34: ...during scanning rtw Reports run time compressions encountered during scanning macrow Reports macros encountered during scanning pwdw Reports password protected files encountered during scanning changew Reports changes encountered during scanning ignlocked Makes the scanner ignore locked files register LICENSE Registers the AVG for Linux E mail Server it is necessary to enter the valid license numb...

Page 35: ... other possibly insecure programs Note If you launch the avgscan command with the clean parameter AVG Anti Virus will attempt to heal all infected files automatically When the healing is successful a VAULT AVG folder is created unless it exists already in the home directory of the user who performed the test The infected files are moved into this directory then whereas the cleaned files remain in ...

Page 36: ...ome user scans the user s home directory including archives reporting uninfected files as OK z avgscan ext rt arc heur home scans the files with any extension in the home directory including the run time compressions and archives Note For online help on the avgscan command type man l opt grisoft avg7 man man1 avgscan 1 gz in your shell 7 2 AVGUPDATE Command Anti virus systems can guarantee reliabl...

Page 37: ...on in the update log file avg7upd log that is to be found in the opt grisoft avg7 var update log directory The avgupdate command is a tool for complex control over the on demand update process The update in general can be performed by launching this command The update properties are controlled using the command options which are listed in the table below General syntax of the command is avgupdate ...

Page 38: ...or detailed information p priority NUM Specifies the priority of an update explicitly the possible priority numbers are 2 priority update 3 recommended update 4 optional update c config FILE Forces use of a configuration file other than the default one etc avg conf The filename with the specified path if necessary is given by the FILE argument i no diff Even when smaller binary diff files are avai...

Page 39: ... of the program s options and usage Return values of avgupdate program are z 0 no errors occurred during the update z 1 nothing new to update z 2 an error occurred during the update Some typical examples of avgupdate use with brief explanations follow z avgupdate o the simple online update z avgupdate f tmp avg updfiles performs the update from the files in the tmp avg udpfiles local directory z a...

Page 40: ...he proper kernel source packages for your distribution Note If you do not have any experience with building the Linux kernel you should not attempt to install DAZUKO unless you get some information and practice in hacking the Linux kernel internals b Compile DAZUKO Once the source code for your running kernel is available you can build DAZUKO You can download the latest version of DAZUKO at http w...

Page 41: ...azuko to the etc modules conf file Insert the module as the root by executing the command sbin insmod dazuko o or sbin insmod dazuko ko for Linux 2 2 2 4 or Linux 2 6 kernels respectively To check if the module has been loaded use the cat proc modules or lsmod grep dazuko command If you see dazuko string along with its device major number usually 254 in the list of modules it is successfully insta...

Page 42: ... stop restart reload status condrestart command The options in the square brackets represent the possible signals that can be sent to the AVG for Linux E mail Server daemons z start starts the daemons z stop stops the daemons z restart restarts the daemons z reload forces the daemons to reload the internal virus database z status shows the status of the daemons z condrestart conditionally restarts...

Page 43: ...options related to the respective section The entries for each section consist of the parameter name and its value or values specified after the character The values can be either numeric integer or strings The numeric 1 0 values usually represent enabling disabling of the respective feature specified by the parameter name Multiple values for one parameter can be separated by white space character...

Page 44: ...e path is required possible values are strings according to the path specification syntax the default value is mnt z excludePath the list of paths ignored by the on access scanner possible values are strings according to the path specification syntax the default value is proc z numOfDaemons the number of on access scanning daemons possible values are non negative integers from 0 to 10 the default ...

Page 45: ...option is enabled as well possible values are strings in the form of user password for example frog swamp to disable this feature leave the default off value z backupDir the location of the backup directory that is used for storing the backup data before performing the update itself possible values are strings according to the path specification syntax the default value is opt grisoft avg7 var upd...

Page 46: ...maximum logging level detailed information on all update phases is recorded useful when an update fails for some unknown reason z timeout specification of the maximum time the download can take in seconds possible values are non negative integers the default value is 0 no limitation posed upon the downloading time ...

Page 47: ...roblem o If there is a problem with e mail processing in general we need to know which e mail server and e mail content scanner AMaViS or Qmail scanner version you use o If some viruses are coming through the e mail server send the virus samples and also the information required in the previous point o If there is a problem with updates set the logging level to 3 in the etc avg conf file and send ...

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